JPH09157593A - Heat-resistant coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a heat-resistant coating material which can form a coating film having both an excellent self-cleaning effect and an excellent deodorizing effect. SOLUTION: An oil and fat decomposition catalyst and a synthetic zeolite adsorbent are added to a coating material containing a polyborosiloxane resin as the binder. It is desirable that the polyborosiloxane resin amounts to at least 5wt.% of the total binder component and that 5-50 pts.wt. oil and fat decomposition catalyst and 3-30 pts.wt. synthetic zeolite adsorbent are used per 100 pts.wt. binder.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a heat resistant coating,
More specifically, it relates to a heat-resistant paint having both self-cleaning properties and deodorizing properties, which are useful for forming a film on the wall surface of a microwave oven or the like.

[0002]

2. Description of the Related Art In recent years, in heating cookers such as microwave ovens and gas tables, it is possible to prevent oil and fat splashing from meat and fish from adhering to the surface when food is cooked and forming a film due to heat and sticking to it. Therefore, by applying and baking a heat-resistant paint containing a decomposition catalyst that promotes the decomposition of fats and oils and a polymerization inhibitor that blocks the initial polymerization of fats and oils due to this decomposition catalyst action, the surface has a so-called self-cleaning effect. Forming a film is performed. Nickel oxide, manganese oxide, etc. are known as decomposition catalysts, antimony oxide, aluminum hydroxide, phosphate frit compounds, etc. are known as polymerization inhibitors, and silicone resins, etc. are known as binding components for paints.

Recently, however, it has been studied to add a self-cleaning effect and a deodorizing effect to the film by further adding an adsorbent to the heat-resistant paint. In this method, a malodorous gas generated when fats and oils are decomposed is adsorbed by an adsorbent, and the adsorbed components are further decomposed by the above-mentioned decomposition catalyst.

[0004]

However, the phosphate frit used as a polymerization inhibitor, for example, cannot be used because it deactivates the adsorption performance of the adsorbent (this is because the frit melted during baking is the adsorbent). It is considered that the activated carbon, which is commonly used as an adsorbent, has poor heat resistance and is not suitable for this application.It still has excellent self-cleaning and deodorizing effects. The fact is that no heat-resistant paint capable of forming a coating film has been obtained.

The present invention has been made in view of the above problems, and an object thereof is to provide a heat resistant coating capable of forming a film having both an excellent self-cleaning effect and a deodorizing effect.

[0006]

The heat-resistant paint of the present invention comprises:
It is characterized in that a paint containing a polyborosiloxane resin as a binder is mixed with an oil and fat decomposition catalyst and a synthetic zeolite adsorbent.

The polyborosiloxane resin used in the present invention is a resin having a structural formula represented by the following formula:
It has both an action as a binder and an action as a polymerization inhibitor at the time of fat and oil decomposition. That is, in the polyborosiloxane resin, the organic group of the side chain is eliminated by heating and baking, and finally it is made inorganic, so that a coating film excellent in heat resistance is formed. Further, the polymerization at the time of decomposing oils and fats is caused by a hydrogen abstraction reaction by a decomposition catalyst to be described later, and in order to suppress this, it is sufficient if there is one that donates a proton. Since there is an OH group bonded to B having a dissociative proton at the end,
As a result of the protons dissociated from the OH groups being provided, the polymerization of fats and oils is blocked. Further, such a polyborosiloxane resin does not have the possibility of deactivating or lowering the adsorption performance of the adsorbent unlike the phosphoric acid frit.

[0008]

Embedded image In the present invention, such a polyborosiloxane resin is preferably used in an amount of at least 5% by weight, more preferably 30% by weight or more, based on the total amount of binder components. If the content of the polyborosiloxane resin is less than 5% by weight based on all the binder components, the effect of the present invention cannot be sufficiently obtained. As the binder component to be used with the polyborosiloxane resin, an inorganic polymer resin that is finally inorganicized by heating and forms a coating film excellent in heat resistance is desirable as in the case of the polyborosiloxane resin. Is a silicone resin,
Polytitanosiloxane resin, polycarbosilane resin, polysilastyrene resin, polysilazane resin, polytitanocarbosilane resin and the like are used.

Next, the fat and oil decomposition catalyst used in the present invention is an oxide of a metal of the fourth period having an oxidation catalytic action and an oxide of an alkali metal and an alkaline earth metal, and specifically, manganese oxide. Metal oxides such as nickel oxide, copper oxide, potassium oxide, sodium oxide and magnesium oxide, solid acid catalysts such as silicon oxide, aluminum oxide and titanium oxide, solid bases such as beryllium oxide, calcium oxide, barium oxide and zinc oxide. Examples include catalysts. These may be used alone,
You may make it mix and use 2 or more types. In the present invention, it is desirable to use manganese dioxide or the like which has a strong oxidation catalytic action.

Further, the adsorbent used in the present invention is a synthetic zeolite adsorbent, which is superior in thermal stability to other adsorbents such as activated carbon and has good compatibility with polyborosiloxane resin. It has features such as Specifically, Zeolum (trade name) manufactured by Tosoh Corporation is used.

The blending amount of these fat and oil decomposition catalyst and synthetic zeolite adsorbent is 5 to 50 parts by weight of fat and oil decomposition catalyst and 3 parts of synthetic zeolite adsorbent per 100 parts by weight of binder.
A range of up to 30 parts by weight is preferred.

In addition to the above components, the coating composition of the present invention may contain pigments, bake hardening catalysts, and other inorganic fillers such as ceramic powders, glass powders, and metal powders as extenders. However, since an adsorbent having a large surface area is blended, if the blending amount is too large, the binder may not be able to retain these additives and the properties as a coating film may be lost. Therefore, it is desirable to consider this point when adding.

Next, the method for producing the heat resistant paint of the present invention will be described.

That is, in the heat-resistant coating material of the present invention, for example, N-methyl-2-pyrrolidone (NM
P), dissolved or dispersed in a polar organic solvent such as dimethylformamide or a nonpolar organic solvent such as toluene or xylene, or mixed by dissolving or dispersing in a similar organic solvent in advance to a liquid state, and thoroughly mixing this It can be obtained by stirring.

The heat-resistant paint of the present invention thus obtained is applied to the surface of the material forming the inner wall of the oven of the microwave oven by a conventional method and baked to obtain a heat-resistant coating excellent in self-cleaning property and deodorizing property. It is possible to form a protective film, prevent sticking of oil and fat that scatters during cooking, and decompose and remove malodorous gas due to decomposition of oil and fat so that it can always be kept in a clean and comfortable use state.

As described above, in the heat-resistant paint of the present invention, the paint containing the polyborosiloxane resin as the binder contains the synthetic zeolite adsorbent together with the fat and oil decomposition catalyst, and the polyborosiloxane resin inhibits the polymerization. Since it also acts as an agent, it does not hinder the adsorption performance of the adsorbent unlike conventional polymerization inhibitors, and can form a polyborosiloxane resin itself and a coating film excellent in heat resistance. The synthetic zeolite adsorbent has good compatibility with such polyborosiloxane resin, and
Since it also has good heat resistance, it is possible to form a heat resistant film having both excellent self-cleaning properties and deodorizing properties.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail by way of examples.

Example 1 80 parts by weight of a 45% by weight NMP solution of a polyborosiloxane resin, 20 parts by weight of a 50% by weight xylene solution of a silicone resin, 20 parts by weight of manganese dioxide, and 20 parts by weight of a zeolite adsorbent (zeolum). Parts and 50 parts by weight of xylene were stirred by a sand mill for 12 hours to obtain a heat resistant coating.

Example 2 The mixing amounts of manganese dioxide and zeolite adsorbent were
A heat-resistant paint was obtained by the same composition and method as in Example 1, except that the amounts were 10 parts by weight and 30 parts by weight, respectively. Then
Each of the resulting heat-resistant paints was applied to the surface of a SUS 430 stainless steel plate by spray coating to a thickness of 10 to 15 μm, and then heated and baked at a temperature of 400 ° C for 10 minutes to prepare a test plate. A performance evaluation test was conducted. The results are shown in Table 1 together with the composition of the coating material and the firing conditions.

In the comparative examples in the table, Comparative Example 1 is an example in which no polyborosiloxane resin is added, Comparative Example 2 is an example in which no zeolite adsorbent is added, and Comparative Example 3 is an example in which manganese dioxide is not added. The test plate prepared in Comparative Example 4 was prepared at a temperature of 550 ° C., Comparative Example 4 was prepared by mixing a conventional polymerization inhibitor (frit of phosphoric acid) in place of the polyborosiloxane resin, and Comparative Example 5 was prepared at Comparative Example 2. This is an example of heating for 10 minutes.

[Performance Evaluation Test] (1) Self-Cleaning Property 50 mg of oil was dropped on a test plate and heated at 300 ° C. for 1 hour, and the loss of oil was measured.

(2) Deodorizing property A test plate (50 mm x 50 mm) was placed in a stainless steel chamber (volume 200 ml) with a built-in heater, and after evacuation, the chamber was replaced with nitrogen gas containing 500 ppm of triethylamine for 30 minutes. After the passage, the concentration of triethylamine was measured. After that, the temperature inside the chamber was further raised to 300 ° C. by a built-in heater, and after 30 minutes, the triethylamine concentration was measured again.

[0023]

[Table 1] As is clear from Table 1, according to the coating materials of Examples, a coating film can be formed by baking under relatively mild conditions, and the coating film thus formed has self-cleaning property and deodorizing property. Both are excellent.

[0024]

As described above, according to the heat resistant coating composition of the present invention, it is possible to form a heat resistant film excellent in both self-cleaning effect and deodorizing effect. Therefore, it is useful as a film forming material on the surface of a heating cooker such as a microwave oven, and these devices can always be kept in a clean and comfortable use state.

[0025]

Claims (4)

[Claims] 1. A heat resistant paint comprising a paint containing a polyborosiloxane resin as a binder, and an oil and fat decomposition catalyst and a synthetic zeolite adsorbent. 2. The heat-resistant paint according to claim 1, characterized in that it contains 5 to 50 parts by weight of a fat and oil decomposition catalyst and 3 to 30 parts by weight of a synthetic zeolite adsorbent per 100 parts by weight of a binder. Heat resistant paint. 3. The heat resistant paint according to claim 1 or 2, wherein the binder comprises a polyborosiloxane resin and another inorganic polymer resin. 4. The heat resistant coating according to claim 1, wherein the content of the polyborosiloxane resin is at least 5% by weight based on all binder components. paint.